fire hazards

• Oxygen + Other Substances = OXIDATION
• Ingredients of Fire

  • Heat
  • Oxidizing agent
  • Uninhibited chemical reaction
  • Fuel
• HEAT

  • Energy
  • Must be enough to vaporize solid and liquid forms of fuel and cause ignition
• Conduction - direct contact
• Convection - flow of liquids and gases
• Radiation - electromagnetic waves
• FUEL 

  • any solid, liquid, or gaseous substance that can be burned
  • must first be converted into the gaseous state
• PYROLYSIS - Solid to Gas Fuel
• VAPORIZATION - Liquid to Gas Fuel
• OXIDIZING AGENT 

  • an element or a compound which releases oxygen or other oxidizers during a chemical reaction.
  • Supports combustion when combined with a fuel.
• UNINHIBITED CHEMICAL CHAIN REACTION

  • Heat given off during combustion is used again to heat the fuel and maintain the burning.
• STAGES OF FIRE

  • IGNITION (INCIPIENT) STAGE
  • GROWTH STAGE
  • FULLY-DEVELOPED FIRE STAGE
  • DECAY STAGE
• IGNITION (INCIPIENT) STAGE

  • 4 requirements are met
  • fire is very small
  • be controlled by a portable fire extinguisher or small hose line, or it may even go out on its own
• GROWTH STAGE

  • Shortest of the four stages
  • Heat release rate increases
• ROLLOVER - Gases rise to the ceiling and cause fire to spread out horizontally burning only gases and not any other material.
• FLASHOVER - non-explosive, abrupt spread of fire through the air to almost all exposed combustible objects.
• FULLY-DEVELOPED FIRE STAGE

  • Fire has consumed almost all of the available combustible materials. Oxygen is being consumed rapidly and maximum temperatures are reached.
• DECAY STAGE

  • Oxygen and fuel begins to diminish.
  • Temperature decrease, fire becomes weaker
• BACKDRAFT - explosive fire that happens due the sudden introduction of oxygen into an enclosed structure.
• Types of Fuel

  • Pyrolysis
  • Vaporization
• WILDFIRE

  • Natural or anthropogenic-cause uncontrolled fire in remote areas where there is extensive combustible vegetation and/or organic material like forests, grasslands, shrublands, etc.
• TYPES OF WILDFIRES

  • GROUND FIRES
  • SURFACE FIRES
  • CROWN FIRES
  • ACCIDENTAL FIRES
  • BUILDING FIRES
• GROUND FIRES

  • Involve burning of buried decomposed organic matter and extensive tree root systems.
• SURFACE FIRES

  • Most common types of burning of fuel scattered on the surface like fallen leaves, branches, bark, stem, and dried-up low-lying vegetation like shrubs and grasses.
• CROWN FIRES

  • Burn tree canopies, other higher parts of trees, and suspended materials like vines.
• ACCIDENTAL FIRES

  • Spontaneous combustion due to extremely hot and dry weather.
• CAUSES of fires

  • Unattended cooking equipment and other household fire sources
  • Electrical appliance and wiring problems
  • Haphazardly stored fammable liquids and other easily combustible materials
  • Firecrackers
  • Arson
• CLASS A

  • Cloth, wood, paper, plastics, rubber, and trash.
  • How to extinguish: for this type of fire simply using water can put out the fire.
• CLASS B

  • LIQUID FUELS - alcohols, gasoline, lacquers, oil-based paint, petroleum oil and grease, solvents
  • GAS FUEL Propane and Butane
• LIQUID FUELS - alcohols, gasoline, lacquers, oil-based paint, petroleum oil and grease, solvents
• GAS FUEL : Propane and Butane
• FIRE TYPES

  • CLASS A
  • CLASS B
  • CLASS C
  • CLASS D
  • CLASS K
• CLASS C

  • Class A & B fuels + powered electrical equipment like home appliances, motors, and transformers.
  • How to extinguish: carbon dioxide or dry chemical agents are usually used. Because of the involvement of electricity, extinguishing this fire type by water is very dangerous and out of the question.
• CLASS D

  • METALS - Aluminum, lithium, magnesium, potassium, sodium, titanium, and zirconium, most of which are usually contained in automobiles.
  • How to extinguish: Salt-based special powders and clean dry sand
• METALS - Aluminum, lithium, magnesium, potassium, sodium, titanium, and zirconium, most of which are usually contained in automobiles.
• CLASS K

  • Cooking oils and greases (animal-and vegetable-fat derived).
  • How to Extinguish: Only a fully-protected firefighter should deal with such fires.
• TYPES OF BURN

  • Superficial burn
  • Partial thickness burn
  • Full thickness burn
• Superficial burn - first degree burns
• Partial thickness burn - second degree burns
• Full thickness burn - third degree burns